Methods and apparatus are provided for mode diversity radio frequency identification (RFAID). The apparatus comprises a first transducer configured to receive a first radio frequency (RF) signal, a second transducer configured to receive an acoustic signal, and an impedance modulator coupled to the first transducer and the second transducer and configured to emit a signal identifying an RFAID tag when the first transducer receives the first RF signal and/or the second transducer receives the acoustic signal. The method comprises transmitting an RF signal and an acoustic frequency signal, and detecting a first modulated signal indicating an RFAID transponder. The first modulated signal is based on one of the RF signal and the acoustic signal.